Locomotive firebox



Patented June 15, 1937 UNlED STATES PATENT OFFIQE 2,083,721 LOCOMOTIVE FIBEBOX poration of Delaware Application June 13, 1936;, Serial No.,85,061

13 Claims.

This invention relates to improvements in locomotive fireboxes and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

The invention is more particularly concerned with fireboxes equipped with one or more thermic syphons and one of the objects of the invention is to provide a novel arrangement of such syphons and their connection with certain of the sheets of the firebox, whereby the superficial area of the firebox is increased, the efiiciency of the steaming action improved, and the water circulation accelerated in the side water legs, thereby preventing formation of any quiescent areas therein.

Another object of the invention is to provide in a firebox, a plurality of thermic syphons, each having inlet portions communicating with both side-water legs of the boiler, with said inlet portions so arranged as to support the brick constituting the arch.

A further object of the invention is to provide a firebox of this kind which is so constructed as to insure flooding of the crown sheet at all times to increase the safety factor under low water conditions.

The above mentioned objects of the invention, as well as others, together with the advantages thereof, will more fully appear as the specification proceeds.

In the drawing:

Fig. 1 is a longitudinal vertical sectional-view through a locomotive firebox embodying the preferred form of the invention.

Fig. 2 is a transverse vertical sectional View through the same as taken on the line 2-2 of Fig. 1.

Fig. 3 is a horizontal detail sectional view as taken on the line 33 of Fig. 1.

Fig. 4 is a horizontal detail sectional view through the inlet end of one of the syphon bodies as taken on the line 44 of Fig. 1.

Referring now in detail to that embodiment of the invention illustrated in the accompanying drawing:

5-5 indicate the side sheets of the firebox, Eindicates the crown sheet, 1 indicates the front orfiue sheet and 8 indicates the back sheet. It will be understood that the firebox is positioned in the rear end of the boiler shell which includes the outer side sheets 9-43, top sheet I0, back sheet I! and front throat sheet [2. Portions of the back sheets 8 and H respectively, are formed to provide a fuel door opening 13.

Several of the various sheets mentioned coact to form the side water legs M, back water leg i5 and front throat 16 respectively, all bottomed by a mud ring ll.. The above is typical of a conventional locomotive boiler rear end structure and requires no further detailed description except to say that companion sheets are suitably staybolted.

Within the firebox are one or more thermic syphons, the number thereof being dependent upon the width and length of the firebox. In this instance four of such syphons, numbered I8, I9, 20 and 2| v respectively are arranged in the firebox. The syphons are disposed two in line on each side of the median plane of the firebox and they are of successively decreasing heights from the, front end rearward.

Each syphon as herein shown includes a substantially flat hollow body 22 of generally a triangular or V shape, disposed parallel with but spaced laterally from the longitudinal median plane of the firebox. The bodies of the second and fourth syphons l9 and 2| from the front end on the otherside of the median line of the firebox are different in size and superficial area, not only with respect to each other, but also with respect to the syphons l9 and 2!. Eachsyphon body 22' has a flanged top 23 fixed in the crown sheet so as to define an outlet or discharge end l8 a I9a--20a and 2h]. respectively, as appears in Fig. 3. It is to be noted that the longer outlet 20a for the syphon body 20 on one side of the firebox is located rearward of the outlet l8a for the syphon body E3 on the same side of the firebox. It is also to be noted that the longer outlet lfia. for the syphon body I9 on the other side of the firebox is located forwardly of the outlet Zia for the syphon body 2| on the same side of the firebox. This staggered arrangement of outlets which best appears in Fig. 3, has advantages in that the plane of the inner ends of the openings I; and 20a. are ofiset longitudinally with respect to the like end of the openings I9a and 2m.

This provides a better arrangement for the staybolts between the crown sheet 6 and top sheet l0 and permits offsetting the transverse lines of welding of the abutting inner ends of the top end flanges 23 of the syphons l8-2ll and I9 and 2! respectively.

The front and rear end walls of each syphon body converge inwardly and downwardly to form inlet ends i3bl9b2fib and 2lb respectively, located at successively decreasing distances downwardly from the crown sheet.

Associated with each syphon body is a duplex inlet member 24-2526 and 2! respectively. Each duplex member is in the form of a transversely extending upwardly arched or convexed tube, the ends of which are secured in and open through both side sheets 5-5. The tube 24 opens at the lowest elevation through the side sheets and the tube 21 opens at the highest elevation through the side sheets. The tube elements 25-25 open through the side sheets at elevations between said highest and lowest elevations. Thus the ends of all of the tubes 26 to 27 inclusive open through the side sheets at successively higher elevations so that said ends are disposed at the longitudinal inclination desired in the arch, soon to be described.

It is pointed out that the bottom ends of the side walls of each syphon merge into or join the top portion of the associated duplex inlet tube by rounded inside corners 28 and 29 of considerable radii, as best appears in Fig. 2. The bottom and inlet end of each body, longitudinally of the firebox, is of a dimension less than the diameter of its associated inlet tube, thus providing a shoulder 30 on the tube upon opposite sides of said bottom end of the body. The convergence of the front and rear walls of each body in connection with the inside rounded corners 2829, gives a substantialy round ended cruciform cross section to the inlet end of each body at this point, as best appears in Fig. 4.

Transverse rows of arch brick 3| are disposed between the adjacent tubular members 24, 25, 26 and 21 respectively, and between the last mentioned member and the bottom portions of the front or flue sheet, to form the fire arch. The front and rear ends of the brick arranged in the plane of the respective syphon bodies, are made to engage and rest upon the tube members and upon the shoulders 30 in such manner as to provide a substantially tight arch without preventing relative movement between adjacent brick under temperature changes.

In the operation of the boiler of which the firebox forms a part, the syphon bodies absorb heat units from the products of combustion and a part of the water in said bodies is converted into steam. Due to the difference in therrnic head thus produced, water is drawn from different points along each side water leg, at different elevations. Said water passes through said tubes into the bottom inlet end of the respective syphon bodies for a discharge out through their outlets onto the crown sheet to keep the same flooded. It is apparent that water in the side water legs is maintained in constant motion and circulation therein, the said legs drawing their supply from both the back water leg, the front throat and the boiler shell respectively. Therefore, an accelerated circulation is established throughout the boiler and this prevents any quiet areas in the boiler or water legs where a settling of the water solids could take place.

By reason of the vigorous circulation established through the side water legs, stresses on the sheets of the firebox, due to expansion and contraction, are equalized and the life of said sheets is greatly prolonged.

If desired, the syphon and its tube member may be made of one piece of sheet metal or t body may be in one piece and the tube may comprise seamless tubing and the two welded together at the inlet end of the body.

By reason of the bow or arch of the tube elements and the inside rounded corners 2829 before mentioned, the parts may move to accommodate the breathing action of the crown sheet due to temperature changes without cracking and without producing ruptures in the side or crown sheets.

While in describing the invention, I have referred in detail to the form, arrangement and construction of the various parts thereof, the same is to be considered only in an illustrative sense so that I do not wish to be limited thereto except as may be specifically set forth in the appended claims.

I claim as my invention:

1. A locomotive firebox embodying therein a crown sheet and side sheets, a plurality of thermic syphons arranged in longitudinally spaced re lation in the firebox and each including a fiat hollow body having a top outlet disposed lengthwise of and opening through the crown sheet, each body having front and rear ends which con verge downwardly to form a bottom inlet for the body, a transversely extending tubular conduit associated with each syphon body and opening at its ends through the side sheets and connected at a point between said side sheets with the bottom inlet of the associated syphon body to provide a duplex inlet neck therefor.

2. A locomotive firebox embodying therein a crown sheet and side sheets, a plurality of thermic syphons arranged in longitudinally spaced relation in the firebox and each including a flat hollow body having a top outlet disposed lengthwise of and opening through the crown sheet, each body having front and rear ends which converge downwardly to form a bottom inlet for the body, and a transversely extending tubular conduit associated with each syphon body and opening at its ends through the side sheets and connected at a point between said side sheets with the bottom inlet of the associated syphon body to provide a duplex inlet neck therefor, and arch brick between and supported upon said transversely extending tubular members.

3. A locomotive firebox embodying therein a crown sheet and side sheets, a plurality of thermic syphons arranged in longitudinally spaced relation in the firebox and each including a flat hollow body, said bodies having different superficial areas and heights from top: to bottom, each body having a top outlet disposed lengthwise of and opening through the crown sheet and having front and rear ends which converge downwardly to form a bottom inlet therefor, transversely extending tubular conduits, one associated with each body and opening at their ends through the respective side sheets at different elevations therein and each connected at a point between the side sheets with the bottom inlet of the associated body to provide a duplex inlet neck therefor.

4. A locomotive firebox embodying therein a crown sheet and side sheets, a plurality of thermic syphons arranged in longitudinally spaced relation in the firebox and each including a fiat hollow body, said bodies being of different superficial areas and heights from top to bottom, each body having a top outlet disposed lengthwise of and opening through the crown sheet and having front and rear ends which converge downwardly to form a bottom inlet therefor, transversely extending tubular conduits, one

iii

associated with each body and opening at their ends through the respectiveside sheets at different elevations therein and each connected at a point between the side sheets with the bottom inlet of the associated body to provide a duplex inlet neck therefor, and arch brick between and supported upon said transversely extending tubular conduits.

5. A locomotive firebox embodying therein a crown sheet and side sheets, a plurality of thermic syphons arranged in longitudinally and laterally spaced relation in the firebox and each includin a fiat hollow body, said bodies being of successively increasing heights from the rear toward the front of the firebox and each having a top outlet disposed lengthwise of and opening through the crown sheet and each having front and rear ends which converge downwardly to form a bottom inlet therefor, the outlets for certain of said bodies having a greater longitudinal dimension than that of others, transversely extending tubular conduits, one associated with each body and opening at the ends through both side sheets, at different elevations therein and each connected at a point between the side sheets with the bottom inlet of the associated body to provide a duplex inlet' neck therefor, and arch brick between and supported upon said. transversely extending conduits.

6. A locomotive firebox embodying therein a crown sheet and side sheets, four thermic syphons arranged in longitudinally spaced relation in the firebox, with two syphons arranged on each side of the longitudinal median plane of the firebox, each syphon including a fiat hollow body, said bodies being of successively increasing heights from the rear toward the front of the firebox and each having a top outlet disposed lengthwise of and opening through the crown sheet, the outlets for certain of said bodies being longer than the outlets for the others, each body also having front and rear ends which converge downwardly to form a bottom inlet therefor, transversely extending tubular conduits, one associated with each body and opening at the ends through the side sheets at elevations arranged according to the inlets of the respective bodies and each connected to the inlet of its associated body to form a duplex inlet neck therefor, and arch brick between and. supported upon said transversely extending conduits.

7. A locomotive firebox embodying therein a crown sheet, side sheets and front and rear sheets respectively, a set of syphons arranged on each side of the median line of the firebox, each set comprising longitudinally spaced substantially aligned syphons each including a flat hollow body, the bodies of said syphons being of different superficial areas and different heights from top to bottom, the bodies in each set each having a top outlet disposed lengthwise of and opening through the crown sheet, and each body having front and rear ends which converge downwardly and inwardly to form a bottom inlet therefor, and means providing conduits leading from certain of said sheets other than the crown sheet and communicating with the inlets of the respective syphon bodies for supplying boiler water thereto.

8. A locomotive firebox embodying therein a crown sheet, side sheets and front and rear sheets respectively, a set of syphons arranged on each side of the median line of the firebox, each set comprising longitudinally spaced, substantially aligned syphons, with the syphons in one set longitudinally offset with respect to those in the other set, each syphon including a fiat hollow body, with the bodies of said syphons differing in superficial areas and heights from top to bottom, the bodies in each set each having a top side of the median line of the firebox, each set" comprising longitudinally spaced substantially aligned syphons each including a fiat hollow body, the bodies of said syphons being of different superficial areas and different heights from top to bottom, the bodies in each set each having a top outlet disposed lengthwise of and opening through the crown sheet, and each body having front and rear ends which converge downwardly and inwardly to form a bottom inlet therefor, and a transversely extending tubular conduit associated with each syphon body and opening at its ends through, the side sheets and connected at a point between said side sheets with the bottom inlet of the associated syphon body to provide a duplex inlet neck therefor.

10. A locomotive firebox embodying therein a crown sheet, side sheets and front and rear sheets respectively, a set of syphons arranged on each side of the median line of the firebox, each set comprising longitudinally spaced, substantially aligned syphons, with the syphon in one set longitudinally offset with respect to those in the other set, each syphon including a fiat hollow body, with the bodies of the said syphons differing in superficial areas and heights from top to bottom, the bodies in each set each having a top outlet disposed lengthwise of and opening through the crown sheet and each body having front and rear ends which converge downwardly and inwardly to form a bottom inlet therefor, and a transversely extending tubular conduit associated with each syphon body and opening at its ends through the side sheets and connected at a point between said side sheets with the bottom inlet of the associated body to provide a duplex inlet neck therefor.

11. A locomotive firebox embodying therein a crown sheet, side sheets and front and rear sheets respectively, a set of syphons arranged on each side of the median line of the firebox, each set comprising longitudinally spaced substantially aligned syphons each including a flat hollow body, the bodies of said syphons being of different superficial areas and difierent heights from top to bottom, the bodies in each set each having a top outlet disposed lengthwise of and opening through the crown sheet and each body having front and rear ends which converge downwardly and inwardly to form a bottom inlet therefor, the outlets for the bodies in each set being relatively long and short respectively with the short outlet of the body on one side of said line substantially opposite the long outlet of the body on the other side of said line, and means providing conduits leading from certain of said sheets other than the crown sheet and communicating with the inlet of the respective syphon bodies for supplying boiler water thereto.

12. A locomotive firebox embodying therein a crown sheet, side sheets and front sheets respectively, a set of syphons arranged on each side of the median line of the firebox, each set comprising longitudinally spaced substantially aligned syphons each including a fiat hollow body, the bodies of said syphcns being of different superficial areas and difierent heights from top to bottom, the bodies in each set each having a top outlet disposed lengthwise of and opening through the crown sheet and each body having front and rear ends which converge downwardly and inwardly to form a bottom inlet therefor, the outlets for the bodies in each set being relativelet of the body on one side of said line substantially opposite the long outlet of the body on the other side of said line, and a transversely extending tubular conduit associated with each syphon body and opening at its ends through the side sheets and connected at a point between 25 said side sheets with the bottom end of the associated syphon body to provide a duplex inlet neck therefor.

13. In a combination with a firebox having a crown sheet and sheets defining water spaces at opposite sides of the firebox extending below the level of the crown sheet, a water circulating and steaming element comprising a single hollow body having a major and a minor dimension providing a substantially elongated outlet disposed longitudinally of the firebox and opening into the space above the crown sheet said body having front and rear ends which converge downwardly to form a bottom inlet end for the body, tubular conduit portions extending substantially transversely of the major dimension of said body, the inner ends of the conduit portions being connected to said bottom inlet of the body to provide the only inlet for the body and the outer ends of said conduit portions opening into the side water spaces but terminating so as not to project substantially into said water spaces, said conduit portions being inclined upwardly from the side water spaces and sweeping into the body of the element at their upper sides.

- BERT E. LARSON. 

